Lizzy Caplan attends the CW, CBS And Showtime 2013 Summer TCA party on July 29, 2013 in Los Angeles, Calif.

Lizzy Caplan has taken on Mean Girls, clingy boyfriends and even blood-sucking vampires! But now, the 31-year-old indie darling is grabbing the reins of an even bigger subject: Sex! Yep, the California-born brunette is starring in Showtime’s newest, racy TV series called Masters of Sex and yes — it's as raunchy as it sounds.

"I never thought I would get used to having a naked woman in front of me masturbating, but I actually broke that barrier on the show," Michael Sheen, who plays researcher William Masters alongside Caplan, said.

So what exactly is Caplan’s newest TV series about? Well, Masters of Sex, which takes places in the mid-20th century, tackles the controversial topic of human sexuality. Researches Virginia Johnson, who is portrayed by Caplan, and her future husband, Masters, spearhead the much-debated topic and perform scientific investigations to explore how sex affects the body and mind.

Cast member Michael Sheen speaks next to co-star Lizzy Caplan at a panel for the television series "Masters of Sex" during the Showtime portion of the Television Critics Association Summer press tour in Beverly Hills, California July 30, 2013.

"Their story is fascinating," the show’s creator, Michelle Ashford, said during Masters of Sex’s first TCA panel on July 30. "We've stuck to the facts very carefully. Certainly the research, we've fudged none of that." Caplan chimed in to say that, despite a bit of comedy, the TV series is not meant to be taken as a comedic story. "We're not really going for a joke. I mean, if you're putting a dildo in front of Beau Bridges' face, people are going to laugh," Caplan conceded. "[The scenes depicted are] factually accurate, and they're what they really did."

The Showtime series is based on Thomas Maier’s 2009 nonfiction book that explores, in depth, Masters and Johnson’s hand-on experiments of sexual intercourse. Instead of the duo questioning people about their sex lives, Masters and Johnson actually “observed volunteers engaging in self-stimulation and sexual intercourse.” Until Maier’s book was released, the sexual pioneer’s research techniques were reportedly a secret.

Caplan explained that her excitement for Masters of Sex to air on the small screen was triggered by the effect Masters and Johnson had on society. "Before Masters and Johnson, people are always telling women that was their fault, and that's some bullsh*t," Caplan said, in regards to the stigma of woman being reserved.